Show me your stripes

The debate that has been raging since the 1870s has finally been solved.

What started as an argument between Charles Darwin and Alfred Russel Wallace has escaped researchers for decades, culminating in several hypothesis. So: Why do zebras have stripes?

Costumes for courtship?

Camouflage to confuse predators?

A natural method of cooling?

Bug repellant?

All four hypotheses have been proposed over the years, but in an NBC news article, the mystery was finally solved. The answer? It’s a bug repellant … at least, that is the current best guess from Tim Caro, a biologist at the University of California.

“It settles the question pretty well, in terms of trying to understand the evolution of striping in horses, zebras and asses,” Caro said.

The study proving such was actually done in 2012. After painting several horse mannequins with a variety of patterns, researchers found that flies gravitated to darker surfaces and away from lighter ones — the blending of patterns were thought to confuse the flies navigational sense.

Caro took the study one step further, attempting to answer why all horses didn’t have such markings if the stripes were so beneficial.

Caro and his team created a map of striped and non-striped species, as well as a map for the blood-sucking insects that targeted the species. The results were that in areas where flies could be active for months at a time (depending on temperature and humidity), striped animals fared well.

“I was surprised myself to see, again and again and again, greater intensity of striping on species and subspecies where we have this biting fly annoyance for months,” Caro added.

And while Caro’s research and some other biologists are tipping in the direction of stripes-as-bug-repellants, others are more skeptical. The other theories are still open for debate, and some scientists are even citing a combination of explanations for the striped pattern.